Commit 0ed17f01 authored by Dave Chinner's avatar Dave Chinner Committed by Darrick J. Wong
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xfs: introduce all-mounts list for cpu hotplug notifications 



The inode inactivation and CIL tracking percpu structures are
per-xfs_mount structures. That means when we get a CPU dead
notification, we need to then iterate all the per-cpu structure
instances to process them. Rather than keeping linked lists of
per-cpu structures in each subsystem, add a list of all xfs_mounts
that the generic xfs_cpu_dead() function will iterate and call into
each subsystem appropriately.

This allows us to handle both per-mount and global XFS percpu state
from xfs_cpu_dead(), and avoids the need to link subsystem
structures that can be easily found from the xfs_mount into their
own global lists.

Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
[djwong: expand some comments about mount list setup ordering rules]
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
parent f1653c2e

fs/xfs/xfs_mount.h

+1 −0
Original line number Diff line number Diff line
@@ -82,6 +82,7 @@ typedef struct xfs_mount { 
	xfs_buftarg_t		*m_ddev_targp;	/* saves taking the address */

	xfs_buftarg_t		*m_logdev_targp;/* ptr to log device */

	xfs_buftarg_t		*m_rtdev_targp;	/* ptr to rt device */

	struct list_head	m_mount_list;	/* global mount list */

	/*

	 * Optional cache of rt summary level per bitmap block with the

	 * invariant that m_rsum_cache[bbno] <= the minimum i for which

fs/xfs/xfs_super.c

+40 −0
Original line number Diff line number Diff line
@@ -49,6 +49,28 @@ static struct kset *xfs_kset; /* top-level xfs sysfs dir */ 
static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */

#endif



#ifdef CONFIG_HOTPLUG_CPU

static LIST_HEAD(xfs_mount_list);

static DEFINE_SPINLOCK(xfs_mount_list_lock);



static inline void xfs_mount_list_add(struct xfs_mount *mp)

{

	spin_lock(&xfs_mount_list_lock);

	list_add(&mp->m_mount_list, &xfs_mount_list);

	spin_unlock(&xfs_mount_list_lock);

}



static inline void xfs_mount_list_del(struct xfs_mount *mp)

{

	spin_lock(&xfs_mount_list_lock);

	list_del(&mp->m_mount_list);

	spin_unlock(&xfs_mount_list_lock);

}

#else /* !CONFIG_HOTPLUG_CPU */

static inline void xfs_mount_list_add(struct xfs_mount *mp) {}

static inline void xfs_mount_list_del(struct xfs_mount *mp) {}

#endif



enum xfs_dax_mode {

	XFS_DAX_INODE = 0,

	XFS_DAX_ALWAYS = 1,
@@ -1038,6 +1060,7 @@ xfs_fs_put_super( 


	xfs_freesb(mp);

	free_percpu(mp->m_stats.xs_stats);

	xfs_mount_list_del(mp);

	xfs_destroy_percpu_counters(mp);

	xfs_destroy_mount_workqueues(mp);

	xfs_close_devices(mp);
@@ -1409,6 +1432,13 @@ xfs_fs_fill_super( 
	if (error)

		goto out_destroy_workqueues;



	/*

	 * All percpu data structures requiring cleanup when a cpu goes offline

	 * must be allocated before adding this @mp to the cpu-dead handler's

	 * mount list.

	 */

	xfs_mount_list_add(mp);



	/* Allocate stats memory before we do operations that might use it */

	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);

	if (!mp->m_stats.xs_stats) {
@@ -1617,6 +1647,7 @@ xfs_fs_fill_super( 
 out_free_stats:

	free_percpu(mp->m_stats.xs_stats);

 out_destroy_counters:

	xfs_mount_list_del(mp);

	xfs_destroy_percpu_counters(mp);

 out_destroy_workqueues:

	xfs_destroy_mount_workqueues(mp);
@@ -2116,6 +2147,15 @@ static int 
xfs_cpu_dead(

	unsigned int		cpu)

{

	struct xfs_mount	*mp, *n;



	spin_lock(&xfs_mount_list_lock);

	list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {

		spin_unlock(&xfs_mount_list_lock);

		/* xfs_subsys_dead(mp, cpu); */

		spin_lock(&xfs_mount_list_lock);

	}

	spin_unlock(&xfs_mount_list_lock);

	return 0;

}